<template>
  <div class="goods">
    <div class="menu-wrapper" ref="menuWrapper">
      <ul>
        <li v-for="(item, index) in goods" class="menu-item" :class="{'current':currentIndex===index}" @click="selectMenu(index, $event)">
          <span class="text border-1px">
            <span v-if="item.type>0" class="icon" :class="classMap[item.type]"></span>{{item.name}}
          </span>
        </li>
      </ul>
    </div>
    <div class="foods-wrapper" ref="foodsWrapper">
      <ul>
        <li v-for="item in goods" class="food-list food-list-hook">
          <h1 class="title">{{item.name}}</h1>
            <ul>
              <li v-for="food in item.foods" class="food-item border-1px" >
                <div class="icon">
                  <img :src="food.icon" width="57" height="57">
                </div>
                <div class="content">
                  <h2 class="name">{{food.name}}</h2>
                  <p class="desc">{{food.description}}</p>
                  <div class="extra">
                    <span class="count">月售{{food.sellCount}}份</span>
                    <span>好评{{food.rating}}%</span>
                  </div>
                  <div class="price">
                    <span class="now">${{food.price}}</span><span v-show="food.oldPrice" class="old">${{food.oldPrice}}</span>
                  </div>
                  <div class="cartcontrol-wrapper">
                    <cartcontrol :food="food"></cartcontrol>
                  </div>
                </div>
              </li>
            </ul>
        </li>
      </ul>
    </div>
    <shopcart :select-foods="selectFoods" :delivery-price="seller.deliveryPrice" :min-price="seller.minPrice"></shopcart>
  </div>
</template>

<script type="text/ecmascript-6">
  import BScroll from 'better-scroll';
  import shopcart from 'components/shopcart/shopcart';
  import cartcontrol from 'components/cartcontrol/cartcontrol'

  const ERR_OK = 0;
  export default {
    data() {
      return {
        goods: [],
        listHeight: [],
        scrollY: 0
      };
    },
    props: {
        seller: {
            type: Object
        }
    },
    created() {
      this.classMap = ['decrease','discount','special','invoice', 'guarantee'];
      this.$http.get('/api/goods').then((response) => {
        response = response.body;
        if (response.errno === ERR_OK) {
          this.goods = response.data;
          this.$nextTick(() => {
            //  更新dom是异步的，需要在这个回调方法里去执行后续代码，否则dom还没更新完
            this._initScroll();
            this._calculateHeight();
          })
        }
      })
    },
    methods: {
        _initScroll() {
          this.menuWrapper = new BScroll(this.$refs.menuWrapper, {
              click:true  //可点击
          });
          this.foodsWrapper = new BScroll(this.$refs.foodsWrapper, {
              click:true,  //可点击
              probeType: 3  //3-监听滚动位置
          });
          this.foodsWrapper.on('scroll', (pos) => {
             this.scrollY = Math.abs(Math.round(pos.y));
          });
        },
      _calculateHeight() {
        let foodList = this.$refs.foodsWrapper.getElementsByClassName("food-list-hook");
        let height = 0;
        this.listHeight.push(height);
        for (let i = 0; i < foodList.length; i ++) {
            let item = foodList[i];
            height += item.clientHeight;
            this.listHeight.push(height);
        }
      },
      selectMenu(index, event) {
        if (!event._constructed) {
            //防止网页，两次点击
            return;
        }
        let foodList = this.$refs.foodsWrapper.getElementsByClassName("food-list-hook");
        let el = foodList[index];
        this.foodsWrapper.scrollToElement(el ,300);
      }
    },
    computed: {
      currentIndex() {
          for (let i = 0; i< this.listHeight.length; i ++) {
              let height = this.listHeight[i];
              let nextHeight = this.listHeight[i + 1];
              if (!nextHeight || (this.scrollY >= height && this.scrollY < nextHeight)) {
                  return i;
              }
          }
        return 0;
      },
      selectFoods() {
        let foods = [];
        this.goods.forEach((goods) => {
          goods.foods.forEach((food) => {
              if (food.count) {
                foods.push(food);
              }
          });
        });
        return foods;
      }
    },
    components: {
      shopcart, cartcontrol
    }
  };
</script>

<style lang="stylus" rel="stylesheet/stylus">
  @import "../../common/stylus/mixin.styl"

  .goods
    display: flex
    position: absolute
    width: 100%
    top: 174px
    bottom: 46px
    overflow: hidden
    .menu-wrapper
      flex: 0 0 80px
      width: 80px
      background: #f3f5f7
      .menu-item
        display:table
        height: 54px
        width: 56px
        line-height: 14px
        padding: 0 12px
        &.current
          position: relative
          margin-top: -1px
          z-index: 10
          background: #fff
          font-weight: 700
          .text
            border-none()
        .icon
          vertical-align : top
          display: inline-block
          width: 12px
          height: 12px
          margin-right: 2px
          background-size: 12px 12px
          background-repeat : no-repeat
          &.decrease
            bg-image('decrease_3')
          &.discount
            bg-image('discount_3')
          &.guarantee
            bg-image('guarantee_3')
          &.invoice
            bg-image('invoice_3')
          &.special
            bg-image('special_3')

        .text
          display: table-cell
          font-size: 12px
          width: 56px;
          vertical-align:middle
          border-1px(rgba(7, 17, 27, 0.1))
    .foods-wrapper
      flex: 1
      .title
        padding-left: 14px
        height: 26px
        line-height: 26px
        border-left: 2px solid #d9dde1
        font-size: 12px
        color:rgb(147, 153, 159)
        background: #f3f5f7
      .food-item
        display: flex
        margin: 18px
        padding-bottom: 18px;
        border-1px(rgba(7, 17, 27, 0.1))
        &:lase-child
          border-none()
          margin-bottom: 0
        .icon
          flex: 0 0 57px
          margin-right: 10px
        .content
          flex: 1
          .name
            margin: 2px 0 8px 0
            height: 14px
            line-height: 14px
            font-size: 14px
            color: rgb(7, 17, 27)
          .desc, .extra
            line-height: 10px
            font-size: 10px
            color: rgb(147, 153, 159)
          .desc
            line-height: 12px
            margin-bottom: 8px
          .extra
            .count
              margin-right: 12px
          .price
            font-weight: 700
            line-height: 24px
            .now
              margin-right: 8px
              font-size: 14px
              color: rgb(240, 20, 20)
            .old
              text-decoration:line-through
              font-size: 10px
              color: rgb(147, 153, 159)
          .cartcontrol-wrapper
            position: absolute
            right: 0
            bottom: 12px

</style>
